package com.dr.common;

import java.math.BigInteger;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

/**
 * 使用md5算法，进行加密
 */
public class MD5Util {
	public static String md5(String plainText) {
		byte[] secretBytes = null;
		try {
			secretBytes = MessageDigest.getInstance("md5").digest(plainText.getBytes());
		} catch (NoSuchAlgorithmException e) {
			throw new RuntimeException("没有md5算法");
		}

		String md5code = new BigInteger(1, secretBytes).toString(16);

		for (int i = 0; i < 32 - secretBytes.length; i++) {
			md5code = "0" + md5code;
		}
		return md5code;
	}
	
	public static void main(String[] args) {
		System.out.println(md5("helloworld"));
	}
}
